将CO2转化为乙烯的分子调整
Fengwang Li1, Arnaud Thevenon2, Alonso Rosas-Hernández2
1Department of Electrical and Computer Engineering, University of Toronto, Toronto, Ontario, Canada.
Nature
|November 21, 2019
概括
研究人员开发了一种分子调节策略,以改善二氧化碳减排的选择性乙烯生产. 这种方法提高了催化剂的性能,从而提高了燃料的效率和可持续性.
科学领域:
- 电化学
- 催化剂
- 可持续能源
背景情况:
- 电催化二氧化碳减排 (CO2RR) 是利用可再生能源储能的一种可持续途径.
- 在CO2RR中实现价值产品如乙烯的高选择性仍然是一个重大挑战.
- 之前的策略集中在催化剂材料的特性上,但乙烯的选择性和能效仍然有限.
研究的目的:
- 开发一种分子调整策略,以提高CO2RR对乙烯的选择性.
- 研究吸附的有机分子对铜催化剂的CO2RR的影响机制.
- 在乙烯电合成中实现高法拉达效率和能源效率.
主要方法:
- 铜电催化剂表面的功能化与来自arylpyridinium电聚变的有机分子.
- 电化学测量,包括操作/现场光谱,以研究催化剂的行为.
- 计算研究以了解反应中间体的稳定性.
主要成果:
- 吸附的有机分子稳定关键的中间体,特别是"顶部结合"的CO中间体,促进乙烯的形成.
- 在中性介质中达到230mA/cm2的高部分电流密度时,乙烯的法拉达效率为72%.
- 使用膜电极组件,经过190小时的稳定乙烯电合成,全细胞能效达20%.
结论:
- 电催化剂表面的分子调节是提高CO2RR选择性的有效策略.
- 这种方法显著提高了乙烯生产的效率和稳定性.
- 这些发现表明通过局部分子控制稳定中间体来设计先进的催化剂的可通用方法.
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